.MERRILL AND TASSix] THE CANYON DIABLO METEORITES 



211 



although the iron oxidizes, with extreme ease and a very short ex- 

 posure to the atmosphere of the room, will cause it to sweat (fig. 2, 

 pi. xix). 



A metallographic description of the eutectic itself cannot satis- 

 factorily be made, since it was found almost impossible to resolve it 

 under the microscope. Practically all that can be said is that the 

 darker-colored alloy is fine granular ; that the grains are apparently 

 homogeneous, and are probably made up of minute octahedra ar- 

 ranged in very fine lamellae. 



The mineralogical separations made on the shale-ball iron did not 

 yield the varied material that the ordinarv Canvon Diablo irons have 



Fig. 49 



yielded. Troilite, magnetite, chromite, diamond, and graphite were 

 not found. 



Schreibersite occurs abundantly in three distinct forms. The most 

 common occurrence is as broad, thin, dark steel-gray, flexible mag- 

 netic lamella?. These are often felted together to such an extent 

 that in one case a mass of them weighing 26 grams has been pre- 

 served intact (text fig. 49). The}' have a specific gravity of 7.090 

 and the following composition : 



P 13.80 



Fe 63 . 04 



Xi 23.07 



Co o . 03 



Cu . 00 



The second occurrence of this phosphide is as more or less flat- 

 tened and angular nodules and rounded grains having a brilliant 



